An electron beam exposure apparatus fixes a wafer to be exposed and corrects its flatness by electrostatically attracting and hold the wafer with an electrostatic chuck.
However, if a wafer with a diameter smaller than that of the electrostatic chuck is placed on the electrostatic chuck and exposed, the following problem occurs. Specifically, electric charges accumulate in a dielectric exposed to the outside in a surface of the electrostatic chuck, which causes a charge-up phenomenon. Then, an electric field generated by the charge-up phenomenon bends an electron beam, so that exposure accuracy deteriorates.
To cope with this, in a conventional electron beam exposure apparatus, an electrostatic chuck is made in conformity with the size of a wafer to be exposed to prevent a dielectric from being exposed to the outside around the wafer.
However, when samples in different sizes are intended to be exposed, the above method requires electrostatic chucks to be changed, and thus requires the apparatus to be modified in a large scale.
The conventional technique therefore has a problem of being unable to easily meet the need for electron beam exposure to samples in various shapes in, for example, trial production.    Patent Document 1: Japanese Laid-Open Patent Publication No. 2008-21686    Patent Document 2: Japanese Laid-Open Patent Publication No. 2004-140297    Patent Document 3: Japanese Laid-Open Patent Publication No. 2010-282825